How many dominoes are in a set?

How many dominoes are in a set? A double-six set has 28 tiles, a double-nine set has 55, and a double-twelve set has 91. Each set contains every unordered pairing from blank–blank through the highest double exactly once.

How many dominoes are in a set by size?

The name “double-N” identifies the largest number on an end. A double-six set uses values zero through six, a double-nine uses zero through nine, and a double-twelve uses zero through twelve.

Set	Values on each end	Total tiles
Double-six	0–6	28
Double-nine	0–9	55
Double-twelve	0–12	91
Double-fifteen	0–15	136
Double-eighteen	0–18	190

Larger sets are extensions of the same system. They are useful when a game needs more hands, longer trains, or more players, but owning more tiles does not mean every game uses all of them.

The domino set formula

For a double-N set, there are N + 1 possible end values because blank counts as a value. The tile count is:

(N + 1)(N + 2) ÷ 2

For double-six, substitute 6: 7 × 8 ÷ 2 = 28. For double-nine: 10 × 11 ÷ 2 = 55. For double-twelve: 13 × 14 ÷ 2 = 91.

This is a triangular-number count. For each value, list that value paired with itself and every greater value. Blank pairs with blank through twelve in a double-twelve set, one pairs with one through twelve, and so on. Because 3–5 and 5–3 are the same physical tile, they are counted once rather than twice.

What is in a double-six dominoes set?

The 28 tiles cover all pairs made from blank, one, two, three, four, five, and six. Seven are doubles: 0–0, 1–1, 2–2, 3–3, 4–4, 5–5, and 6–6. The other 21 have different ends.

Each value appears on seven distinct tiles: six appears on 6–blank through 6–6, for example. When individual ends are counted, the double contributes the number twice, so distinguish “tiles containing six” from “six-pip ends.”

Double-six is the traditional compact choice for many two-to-four-player Block, Draw, and All Fives games. Exact hand sizes and unused stock depend on the named rules.

What is in a double-nine dominoes set?

A double-nine set has ten end values and 55 tiles. It contains ten doubles and 45 mixed-number tiles. It supports larger hands or more players than double-six without becoming as large as a train-game set.

Some groups use double-nine for five or six players, partnership games, or train variants. There is no universal mapping from a player count to a set size; a published game’s component list should control.

What is in a double-twelve dominoes set?

A double-twelve set has 91 tiles: 13 doubles and 78 tiles with unlike ends. It is widely used for Mexican Train and Chicken Foot, especially when several people play. A full descending game can use starting rounds from 12–12 through blank–blank.

Not every round places every tile. Hand size, player count, and draw rules decide how much remains in the boneyard.

Counting a set without listing every tile

To check whether a set is complete, sort by the lower end. The blank group should contain blank–blank through blank–N, for N + 1 tiles. The one group then contains 1–1 through 1–N, one fewer tile. Continue until the final group contains only N–N.

For double-six, the group sizes are 7 + 6 + 5 + 4 + 3 + 2 + 1 = 28. For double-twelve, they descend from 13 to 1 and total 91. This method exposes a missing tile without relying on pip color, which can differ by manufacturer.

Set size is not hand size

The set count describes all available tiles, not the number dealt. A two-player double-six game commonly deals seven each, leaving 14 undealt. A four-player partnership game may deal all seven to each player, leaving no stock. Another four-player ruleset may deal fewer and retain a boneyard.

Domino Scoreboard is a score keeper for real tabletop games covering five modes: Block, Draw, All Fives, Mexican Train, and Chicken Foot.

Choosing the right set

Use double-six for a classic compact game unless the rules call for more values. Choose double-nine when additional players or a specific variant needs 55 tiles. Double-twelve is the common practical choice for long train and Chicken Foot formats.

Avoid combining two identical sets unless the game explicitly permits duplicate tiles. Standard matching games assume that each numerical pairing appears once, and duplicates invalidate normal tile-count deductions.

FAQ

Why are there 28 dominoes in a set?

A double-six set has seven values, zero through six, and every unordered pair appears once. The calculation is 7 × 8 ÷ 2 = 28.

How many doubles are in a double-six set?

Seven. There is one double for every value: blank through six.

Are all domino sets 28 pieces?

No. Twenty-eight describes double-six; double-nine has 55 and double-twelve has 91. Even larger extended sets also exist.

Does a blank count as a number in the set?

Yes. For construction and matching, blank is the zero value. That is why double-six has seven possible end values rather than six.